We present HST STIS measurements of the interstellar O
I, Mg II, P II, Mn II, Ni II, Cu II, Ge II, and Kr I
absorption lines in over 40 sight lines with pathlengths of
up to 5 kpc through the Galactic disk. Utilizing targeted
and archival FUSE data, we have also obtained H2
measurements for over half of our sight lines. A trend
toward lower gas-phase elemental abundance ratios with
increasing mean total hydrogen sight line density (< nH
> = N(H)/d) is evident for each element except krypton.
Although such trends have previously been identified by
Copernicus measurements, they are more distinct in our
STIS/FUSE data which benefit from the improved measurement
capabilities of these instruments. The case of oxygen in low
density sight lines (< nH > less than 1 cm-3) is
particularly intriguing. Although there is no trend with <
nH > in this sample, shorter sight lines (d < 750 pc)
have about 0.15 dex lower gas-phase oxygen abundances than
for longer sight lines. In addition, we report the first
sight line (HD152590) with an apparently solar Kr/H ratio.
Since the inferred depletions for other elements in this
sight line are characteristic of the cold ISM, the krypton
enhancement appears to be a nucleosynthetic effect.

Financial support for this work was provided by the Space
Telescope Science Institute through grants to Northwestern
Univerisity and Whitman College.